Sound transmitting and receiving device.



No. 652 926. Patented July 3, I900.

c." SALMOND.

SOUND TRANSMITTING AND RECEIVING DEVICE.

(Application filed Sept. 7, 1899.)

(No Iode l.)

WITNESSES 1N VEN TOR.

Ya: mum: PEYERS co, PHOTO-UTHO" WASHINGTON. n c.

UNITED STATES PATENT OFFICE.

COLIN SALMOND, OF SAN'FRANCISOO, CALIFORNIA.

SOUND TRANSMITTING AND RECEIVING DEVICE.

SPECIFICATION forming part of Letters Patent No. 652,926, dated July 3,1900.

Application filed September 7,1899. Serial No. 729,786. (No model.)

To (all whom, it may concern:

Be it known that I, COLIN SALMoND, a citizen of the United States,residing at San Francisco, in the county of San Francisco and State ofCalifornia, have invented certain new and useful Improvements in SoundTransmitting and Receiving Instruments; and I do hereby declare thefollowing to be afull, clear, and exact description of saidinvention,such as will enable others skilled in the art to which it mostnearly appertains to make, use, and practice the same.

This invention relates to improvements in sound transmitting andreceiving instruments.

In the drawings, Figure 1 is a side view of the preferred form of aconstruction embodying the invention in the form of an attachment to amegaphone. of a megaphone having this attachment secured thereto. Fig. 3is a side view of an alternative construction. Fig. 4 is a longitudinalsection of the mouthpiece, showing the shutters for cutting out themouthpiece and the earpiece. Fig. 5 is a cross-section of the same,taken on the line X X in Fig. 4.

The object which the present invention has in View is to enable the userof a speakingtrumpet, megaphone, or like instrument to receive soundswithout moving the instrument from the speaking position or the positionin which it is directed toward the object at which the sound wasprojected and from whence the sound in reply would emanate. By theaccomplishment of this object the greatest objection in the use of thischaracter of instruments is avoided. In their present use theseinstruments are alternately utilized for sound transmitting and forsound receiving. In the former instance the user directs the instrumentas he looks at the object. After speaking he turns his head and placesthe mouthpiece of the instrument to his ear to receive the sounds inreply. In the latter adjustment the direction of the instrument is onlyapproximately correct. when not aecurately correct or turned directlytoward the object from whence the sound emanates,these instruments donot receive the full volume of the sound.

The presentinvention consists in providing Fig. 2 is a side View aninstrument of the character specified with a tubular extension, at theend of which is provided an earpiece to rest opposite the ear or whichmay be placed opposite the ear while the instrument is in position to beused for close the passage of the tubular extension where the passage ofthe mouthpiece is open and to close the passage of the mouthpiece whenthe passage of the extension is open.

To facilitate the description of the invention with reference to thedrawings, I will let the letter A designate a megaphone, to which thisinvention is applied. It is provided with a mouthpiece B,constructed,preferably, of metal. Into this mouthpiece is inserted theplug B until the flange B rests against the flange of the mouthpiece. Ifdesired, the plug B may be permanently secured in the mouthpiece bysolder or rivets. Beyond the flange B is extended the short tube 13 atthe end of which is provided the mouthpiece 13. Extended out at ananglefrom the side of the tube B is the branch tube G, which in the preferredform is constructed of a stiff material, such as metal, and is bent, asshown in the drawings, to hold the earpiece D against the ear of theuser of theinstrument when speakinginto the mouthpiece B. The earpiece Dis made of any suit able construction.

In some instances it is preferred to substitute for the rigid tube G theflexible tube E. (Shown in Fig. 3.) When using the instrument thusprovided with the flexible tube, the user is compelled to hold with onehand the earpiece D in position. This form of construction has anadvantage in that the construction is more economical, not necessitatinga gate to shut 01f the passage E and 0 While the instrument is beingspoken into.

WVith this construction the earpiece may be removed from the car whilespeaking and placed to the car when listening.

In the constructions where the tube 0 is rigid I use the double gate FF. The gate F is a disk which fits over the mouthpiece B and is carriedby the pivot F the end of which is bent to form a crank F by which thegates may be opened or closed. The gate F is normally maintained closedby a spring F ,which is mounted about the pivot F in such a manner thatthe expansion of the spring rotates the pivot to close the gate F. Thegate F is mounted on the inner side of the gate F and is elongated tocover the opening of the tube 0 into the passage of the mouthpiece whenthe gates are swung so that the passage of the mouthpiece is open, asshown in Fig. 5 of the drawings. To more perfectly close the passages ofthe mouthpiece B or the tube 0, these gates may be provided with ayielding surface, such as chamois-skin or cork. By this constructionwhen either of the passages is completely closed by the gate the otherpassage is completely open.

While I have shown and described the construction as operating tonormally close the mouthpiece by the action of the spring F it will beunderstood that this may be removed; also, the construction may bealtered so that the added piece constituting the gate F may be dispensedwith by using the reverse or inner side of the gate F to close thepassage of the tube 0. When thus provided with the described gate orgates, the manner of using the invention is as follows: The operator onseeing the object at which the sounds are to be directed raisestheinstrument to his mouth, with the earpiece opposite or restingagainst his car. He then presses on the crank F to throw the gate F toopen the passage of the mouthpiece B and close the passage of the tube0. Having finished speaking, he releases the crank, and the gate Finstantly closes the passage of the mouthpiece, while opening thepassage of the tube 0.

In'this position the instrument will receive the full volume of sound,as it is maintained in the original position.

Having thus described this invention, what is claimed is v 1. Thecombination with an unsupported trumpet-like sound receiving andtransmitting instrument having a mouthpiece, of a branch pipecommunicating with the air-passage in the smaller end of the instrumentand provided with an earpiece; substantially as described.

2. In a sound receiving and transmitting instrument, a pipe providedwith a mouthpiece, a branch pipe communicating with said first-mentionedpipe and provided with an earpiece, and means for maintaining one ofsaid pipes closed during the time the other of said pipes is open foruse; substantially as described.

3. In a sound receiving and transmitting instrument, a pipe providedwith a mouthpiece, abranch pipe communicating with said first-mentionedpipe and provided with an earpiece, and a gate pivoted between theopenings in the said pipes and adapted to be swung to close either ofsaid pipes and thus leave the other pipe open, said gate being providedwith means for holding it in position to close either pipe during theperiod of use of the other pipe; substantially as described.

In a sound receiving and transmitting instrument, a pipe provided with amouthpiece, a branch pipe communicating with said first-mentioned pipeand provided with an earpiece, and a member normally yieldinglymaintained in position to close the first-mentioned pipe, saidsecond-mentioned pipe being normally open 5 substantially as described.

In testimony whereof I have hereunto set my hand this 28th day of July,1899.

COLIN SALMOND.

\Vitnesses:

E. F. MURDocK, BALDWIN VALE.

